Global Patent Index - EP 1034451 A1

EP 1034451 A1 2000-09-13 - FERROELECTRIC LIQUID CRYSTAL DEVICES WITH TWISTED STRUCTURE

Title (en)

FERROELECTRIC LIQUID CRYSTAL DEVICES WITH TWISTED STRUCTURE

Title (de)

FERROELEKTRISCHE FLÜSSIGKRISTALLVORRICHTUNG MIT VERDRILLTER STRUKTUR

Title (fr)

DISPOSITIFS A CRISTAUX LIQUIDES FERROELECTRIQUES A STRUCTURES TORSADEES

Publication

EP 1034451 A1 (EN)

Application

EP 98961785 A

Priority

  • US 9825158 W
  • US 98044797 A

Abstract (en)

[origin: WO9928778A1] A hybrid analog/binary electro-optic modulator using a twisted ferroelectric liquid crystal structure is provided. Ferroelectric liquid crystals with a tilt angle of between about 20 DEG and about 25 DEG , preferably about 22.5 DEG are used. Rubbing directions for the two cell walls (relative to one another) can be varied from about 45 DEG to about 90 DEG . In one embodiment, a weak buffing force is used resulting in a relatively weak anchoring energy at the surface, aligning the liquid crystal molecules without locking the molecules into the buffing directions and a high pre-tilt structure for the molecules close to the surface boundaries. In one embodiment, strong buffing is used with buffing directions offset about 45 DEG . Use of this invention provides relatively fast response time, low required driving voltage, high contrast, and/or the ability to achieve both analog and binary operations.

IPC 1-7 (main, further and additional classification)

G02B 26/02; C09K 19/02; G02F 1/1333

IPC 8 full level (invention and additional information)

G02F 1/137 (2006.01); C09K 19/02 (2006.01); G02F 1/141 (2006.01); G02F 1/31 (2006.01)

CPC (invention and additional information)

C09K 19/0225 (2013.01); G02F 1/141 (2013.01); G02F 1/31 (2013.01)

Citation (search report)

See references of WO 9928778A1

Designated contracting state (EPC)

DE FR GB IT NL

EPO simple patent family

WO 9928778 A1 19990610; AU 1702599 A 19990616; CA 2308199 A1 19990610; EP 1034451 A1 20000913; JP 2001525560 A 20011211; US 6141076 A 20001031

INPADOC legal status


2003-12-10 [18D] DEEMED TO BE WITHDRAWN

- Ref Legal Event Code: 18D

- Effective date: 20030602

2000-12-20 [RIN1] INVENTOR (CORRECTION)

- Ref Legal Event Code: RIN1

- Inventor name: LIU, JIAN-YU

2000-12-20 [RIN1] INVENTOR (CORRECTION)

- Ref Legal Event Code: RIN1

- Inventor name: WU, KUANG-YI

2000-12-20 [RIN1] INVENTOR (CORRECTION)

- Ref Legal Event Code: RIN1

- Inventor name: WONG, CHARLES

2000-09-13 [17P] REQUEST FOR EXAMINATION FILED

- Ref Legal Event Code: 17P

- Effective date: 20000609

2000-09-13 [AK] DESIGNATED CONTRACTING STATES:

- Ref Legal Event Code: AK

- Designated State(s): DE FR GB IT NL